JP2017059646A - Magnetic composite material, inductor element and manufacturing method for magnetic composite material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a magnetic composite material with a low coercive force.SOLUTION: The magnetic composite material includes a plurality of magnetic metal particles containing at least one type of magnetic metal selected from Fe, Ni and Co; at least one type selected from metal oxide, nitride, carbide and fluoride. An average grain diameter of the magnetic composite material is 0.1 μm to 40 μm and an average grain diameter of each of the plurality of magnetic metal particles in a surface of the magnetic composite material is not more than 80 nm.SELECTED DRAWING: Figure 1

Description

  Embodiments described herein relate generally to a magnetic composite material, an inductor element, and a method for manufacturing a magnetic composite material.

  In recent years, with the rapid increase in communication information, electronic communication devices have been reduced in size and weight. In connection with this, size reduction and weight reduction of an electronic component are desired.

  A normal high magnetic permeability member is a metal or alloy containing Fe or Co as a component, or an oxide thereof. A metal or alloy high permeability member becomes difficult to use as a component because the transmission loss due to eddy current becomes significant as the frequency increases. On the other hand, when an oxide magnetic material typified by ferrite is used as a component, loss due to eddy current is suppressed because of high resistance, but since the resonance frequency is several hundred MHz, transmission loss due to resonance is high at high frequencies. It becomes noticeable and difficult to use. For this reason, as a component, an insulating high magnetic permeability member that suppresses a loss that can be used even for a high frequency as much as possible is required.

  As an attempt to produce such a high magnetic permeability member, a high magnetic permeability nano-granular material has been produced using thin film technology such as sputtering, and it has been confirmed that it exhibits excellent characteristics even in a high frequency region. However, in the granular structure, it is difficult to improve the volume percentage of the magnetic fine particles while maintaining high resistance, and furthermore, it is difficult to obtain the volume as a component, so it is difficult to produce the component with the current thin film technology. it is conceivable that.

  Therefore, there is an attempt to produce a high permeability thick film nano-granular material by forming a magnetic metal material into nanoparticles and dispersing it in an insulator. When this material is used, as a result of various antenna prototypes, it is said that there is a possibility that a high-performance antenna having a small size and high receiving sensitivity may be realized when used as a magnetic core of a helical antenna.

  However, when this material is used not for low-power components such as antennas but for high-power components, not only eddy currents but also hysteresis loss of the magnetic material cannot be ignored, which hinders practical application. The hysteresis loss is related to the coercive force. The greater the coercive force, the greater the hysteresis loss, and how to suppress this is a problem.

  On the other hand, a structure (heterogranular structure) in which magnetic nanoparticles containing an insulating phase are combined and dispersed in the insulator can be made. However, because the coercive force is large due to internal stress etc. and the loss is large, high permeability at high frequencies cannot be obtained, and it was mainly used for applications such as radio wave absorbers that use loss components. For example, it could not be used for applications requiring low loss and high magnetic permeability such as inductors.

JP 2001-358493 A Japanese Patent No. 517584

  The problem to be solved by the present invention is to provide a magnetic composite material having a low coercive force.

  The magnetic composite material of the embodiment includes a plurality of magnetic metal particles including at least one magnetic metal selected from Fe, Ni, and Co, and at least one selected from metal oxide, nitride, carbide, or fluoride. The average particle size of the magnetic composite material is 0.1 μm or more and 40 μm or less, and the average particle size of the plurality of magnetic metal particles on the surface of the magnetic composite material is 80 nm or less.

It is a schematic diagram of the magnetic composite material of 1st Embodiment. It is a microscope picture of the magnetic composite material of 1st Embodiment. It is a schematic diagram of the chip inductor element of the second embodiment. It is a schematic diagram of the inductor element for transformer of the second embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
The magnetic composite material of this embodiment includes a plurality of magnetic metal particles containing at least one magnetic metal selected from Fe (iron), Ni (nickel), and Co (cobalt), and metal oxides, nitrides, and carbides. Or at least one selected from fluorides, wherein the magnetic material has an average particle size of 0.1 μm or more and 40 μm or less, and an average particle of a plurality of magnetic metal particles on the surface of the magnetic composite material The diameter is 80 nm or less.

  The magnetic composite material of this embodiment may be referred to as heterogranular particles.

  FIG. 1 is a schematic view of a magnetic composite material 100 according to an embodiment. Magnetic metal particles 10 (particles observed on the surface) on the surface of the magnetic composite material 100 are indicated by solid lines. A schematic diagram of a part of the magnetic composite material 100 is omitted. FIG. 2 is a photomicrograph of the magnetic composite material 100 of the embodiment. FIGS. 2A and 2B are SEM (Scanning Electron Microscope) photographs taken at a magnification of 100,000 times. The white dotted line shown in FIG. 2 (a) indicates the magnetic metal particles on the surface of the magnetic composite material in FIG. 2 (b).

  The magnetic metal particle 10 includes at least one magnetic metal selected from Fe, Ni, and Co. The element that becomes the magnetic metal is, for example, Fe, Ni, or Co. Among these, Fe-based alloys, Co-based alloys, and FeCo-based alloys that can realize high saturation magnetization are particularly preferable.

  Fe-based alloys and Co-based alloys include FeNi alloys, FeMn alloys, FeCu alloys, FeMo alloys containing Ni, Mn (manganese), Cu (copper), Mo (molybdenum), Cr (chromium), etc. as the second component. FeCr alloy, CoNi alloy, CoMn alloy, CoCu alloy, CoMo alloy, and CoCr alloy. Examples of the FeCo-based alloy include alloys containing Ni, Mn, Cu, Mo, and Cr as the second component. These second components are effective components for improving the magnetic permeability.

  The magnetic metal particle 10 may further contain a nonmagnetic metal. Nonmagnetic metals include Mg (magnesium), Al (aluminum), Si (silicon), Ca (calcium), Zr (zirconium), Ti (titanium), Hf (hafnium), Zn (zinc), Mn (manganese), Ba (barium), Sr (strontium), Cr (chromium), Mo (molybdenum), Ag (silver), Ga (gallium), Sc (scandium), V (vanadium), Y (yttrium), Nb (niobium), It is at least one or more metals selected from Pb (lead), Cu (copper), In (indium), Sn (tin), and rare earth elements. These non-magnetic metals are elements that have small Gibbs energy of standard generation and are easily oxidized, and are oxide coating layers that coat the magnetic metal particles 10 (this oxide coating layer is one of the constituent components of the magnetic metal particles 10). From the viewpoint of the insulating stability of the oxide or composite oxide containing one or more nonmagnetic metals, it is a preferable element. Among them, Al and Si are preferable from the viewpoint of thermal stability because they are easily dissolved in solid solution with Fe, Co, and Ni which are the main components of the magnetic metal particles 10.

  The magnetic metal particles 10 may further contain at least one of carbon and nitrogen (carbon alone, nitrogen alone, or both carbon and nitrogen may be used). Carbon and nitrogen are effective elements that can increase magnetic anisotropy by solid solution with magnetic metal. A material having a large magnetic anisotropy can increase the ferromagnetic resonance frequency (μ ′ of the material greatly decreases near the ferromagnetic resonance frequency and μ ″ greatly increases) and can be used in a high frequency band. It becomes a possible material.

  The content of the nonmagnetic metal, carbon, and nitrogen contained in the magnetic metal particle 10 is 20 at% or less with respect to the magnetic metal. If the content is more than that, the saturation magnetization of the magnetic metal particles 10 is lowered, which is not preferable. In addition, it is preferable that the magnetic metal, the nonmagnetic metal, and at least one of carbon and nitrogen contained in the magnetic metal particle 10 are in solid solution. By solid solution, the magnetic anisotropy can be effectively improved, thereby improving the high frequency magnetic characteristics. In addition, the mechanical properties of the material can be improved. If it does not form a solid solution, it segregates at the grain boundaries and surface of the magnetic metal particles, and the magnetic anisotropy and mechanical properties cannot be improved effectively.

  The magnetic metal particles 10 may be either polycrystalline particles or single crystal particles, but single crystal particles are preferred. By using single crystal particles, the easy axis of magnetization can be aligned when the particles are integrated, so that the magnetic anisotropy can be controlled and the high frequency characteristics are better than in the case of polycrystal.

  The magnetic metal particle 10 may be a particle aggregate. The average particle diameter of the primary particles may be 10 nm or more, and these may be aggregated to form a particle aggregate having an average particle diameter of 1 μm or more. Moreover, at least 1 sort (s) chosen from an oxide layer, a nitride layer, a carbide | carbonized_material layer, or a fluoride layer may interpose between primary particles. These are high resistance layers. When the thickness of the intervening layer is ideally 1 nm or less, the coercive force can be reduced because the primary particles are magnetically coupled to each other. If the aspect ratio is further increased, a synergistic effect can be obtained.

  The magnetic metal particle 10 may be amorphous. It may be a single metal or an alloy, or may be an amorphous mixed with an insulator such as an oxide, nitride, or carbide.

  Part of the magnetic metal particles 10 may have an oxide coating layer made of constituent elements of the magnetic metal particles. The thickness of the oxide coating layer is not particularly limited, but is preferably 0.1 nm or more and 100 nm or less. If it is less than 0.1 nm, the oxidation resistance is insufficient, and thus handling is difficult. There is a possibility that problems such as oxidation and heat generation occur at the same time as opening in the air, which is not preferable. Further, when the thickness exceeds 100 nm, when the member is made by integrating the particles, the filling rate of the magnetic metal particles contained in the member is lowered, the saturation magnetization of the member is lowered, and thereby the permeability is lowered. It is not preferable. The thickness of the oxide coating layer that is stable against oxidation and that is effective for not significantly decreasing the saturation magnetization or the magnetic permeability is 0.1 nm or more and 100 nm or less.

  Similarly, a part of the surface of the magnetic metal particle 10 may be provided with at least one layer of nitride, carbide or fluoride. Each of the layers may contain B, Ta, W, P, and Ga. The thickness of each layer is not particularly limited, but is the same as in the case of the oxide coating layer.

  At least one kind 20 selected from metal oxides, nitrides, carbides or fluorides is provided around the plurality of magnetic metal particles 10. At least one kind 20 selected from oxides, nitrides, carbides or fluorides of these metals includes oxides, nitrides, carbides or fluorides. More preferably, Fe, Ni, Co, Mg, Al, Si, Ca, Zr, Ti, Hf, Zn, Mn, Ba, Sr, Cr, Mo, Ag, Ga, Sc, V, Y, Nb, Pb, It contains at least one element selected from oxide, nitride, carbide or fluoride containing at least one element selected from Cu, In, Sn and rare earth elements.

  In order to use the magnetic composite material 100 at a high frequency of 100 kHz or higher, the average particle size is preferably 0.1 μm or more and 40 μm or less, more preferably 0.1 μm or more and 10 μm. In particular, it is preferable that the particle diameter is in the range of 0.1 μm or more and 40 μm or less.

  The average particle diameter of the plurality of magnetic metal particles 10 on the surface of the magnetic composite material 100 is preferably 80 nm or less in order to obtain a magnetic composite material having a small coercive force. In order to further reduce the coercive force, 50 nm or less is preferable, and 30 nm or less is more preferable. On the other hand, if the thickness is smaller than 5 nm, the effect of superparamagnetism is exerted and the characteristics are changed.

  The crystal diameter of the magnetic metal particles 10 is preferably 1 nm or more and 50 nm or less because of low loss at high frequencies. More preferably, it is 5 nm or more and 30 nm or less because of low loss at high frequency while suppressing the influence of superparamagnetism.

  The aspect ratio of the magnetic composite material 100 is preferably 1 or more and 5 or less, and more preferably 1 or more and 3 or less. Although the reason for this is not clear, it is expected that some distortion occurs in the magnetic material 100 having a high aspect ratio, which increases the coercive force.

  In the magnetic composite material 100 of this embodiment, the material structure is SEM, TEM (Transmission Electron Microscope), and the diffraction pattern (including confirmation of solid solution) is TEM-Diffraction, XRD (X-ray Diffraction). : X-ray diffraction), and identification and quantitative analysis of constituent elements are ICP (Inductively coupled plasma) emission analysis, XRF (X-ray Fluorescence Analysis), EPMA (Electron Probe Micros: Analyze) Electron beam microanalyzer), EDX (Energy Dispersive X-ray), Fluore Each of them can be discriminated with a sequence spectrometer or the like.

  The average particle diameter of the magnetic composite material 100 of this embodiment is determined by measuring the longest diameter by observation with an SEM. For example, it is uniquely determined if it is a sphere, but if it is indefinite or flat, the longest diameter is selected. The aspect ratio of the magnetic material 100 of this embodiment is obtained using the longest and shortest values of the diameters measured in this way.

  The average particle size of the plurality of magnetic metal particles 10 on the surface of the magnetic composite material 100 is the average of the longest and shortest diagonals of the particles on each surface by SEM observation of 100,000 times (100,000 times). The particle diameter is obtained from the average of 10 particle diameters. An example of the magnetic metal particle 10 on the surface is shown by a region surrounded by a white dotted line in FIG.

  The crystal diameter of the magnetic metal particle 10 is obtained from the Scherrer equation using the XRD measurement result.

  Next, a method for manufacturing the magnetic composite material 100 of this embodiment will be described.

  The manufacturing method of the magnetic composite material of this embodiment includes an alloy containing at least one magnetic metal selected from Fe, Ni, and Co, and Mg, Al, Si, Ca, Zr, Ti, Hf, Zn, Mn, and Ba. , Sr, Cr, Mo, Ag, Ga, Sc, V, Y, Nb, Pb, Cu, In, Sn, at least one element selected from rare earth elements, and oxygen (O), nitrogen (N), or carbon (C) Magnetic composite nanoparticles containing any of (C) are aggregated and integrated by stirring together with media in a dry manner in a container, and a step of producing a magnetic composite material having a larger diameter is stopped for a predetermined time. And a process.

  First, the process of synthesizing magnetic composite nanoparticles will be described. Although this process is not particularly limited, preferred examples include a dry synthesis method represented by a high-frequency induction thermal plasma method and a laser ablation method, and a wet synthesis method represented by a coprecipitation method. The diameter of the magnetic composite nanoparticle is smaller than the average particle diameter of the magnetic composite material 100 and is 10 nm or more and 100 nm or less.

  The synthesized magnetic composite nanoparticles are preferably coated with carbon or the like. The reason is that the synthesized magnetic composite nanoparticles are very active and oxidize and burn when exposed to air. However, no special coating of carbon or the like is required by handling in an inert gas, in a vacuum, or in a liquid with low reactivity. Further, for example, when carbon is coated, it is necessary to gasify and remove the carbon by heating / reducing treatment. This is because the residual carbon is not suitable as an insulating material because of its conductivity.

Furthermore, the magnetic composite nanoparticles are preferably covered with a coating layer, that is, formed into a core shell. For example, it is preferable that a coating layer containing, for example, Al ₂ O ₃ is formed by forming an oxide film by leaving it in an inert gas having a very low oxygen concentration, so that it is in a relatively stable state. In addition, the coating layer may be formed by nitriding and carbonizing.

  Next, a step of producing a magnetic composite material having a larger diameter by aggregating magnetic composite nanoparticles by agitation with media in a container in a dry manner and a step of stopping the stirring for a predetermined time will be described. To do.

  To produce a magnetic material with a larger diameter by stirring together with media in an oxidizing atmosphere container, for example, encapsulate media such as magnetic composite nanoparticles and balls in a predetermined container of a planetary ball mill. It can be carried out by preparing a magnetic composite nanoparticle aggregate by stirring in a dry method in which the solvent is not enclosed in the container, but in a dry method in which the solvent is not enclosed in the container. This oxidizing atmosphere can be performed in an inert atmosphere (for example, Ar atmosphere) having an oxygen content of several ppm. By this step, the element constituting the magnetic metal particle becomes a magnetic composite material including an oxide depending on the atmosphere.

  In addition, the nitride, carbide or fluoride particles of magnetic metal particles and the magnetic metal particles as raw materials are stirred together with the media in a container in an inert gas atmosphere, for example, Ar atmosphere, so that the metal nitride, carbide or fluoride is stirred. It becomes a magnetic composite material provided with at least 1 sort (s) chosen from these.

  As the container, known containers such as agate, alumina, zirconia, or silicon nitride can be preferably used.

  However, it is difficult to manufacture the magnetic composite material 100 of the present embodiment only by a method using a medium such as the above-described ordinary planetary ball mill. This is because it is difficult to recover the magnetic material because all of the magnetic material sticks to the ball and the container wall only by this normal method. This is because it is difficult to obtain a magnetic material with low magnetic loss because the particle size and the internal structure of the particle cannot be controlled even if the particles are forcibly peeled off and collected.

  In the manufacturing method of the magnetic composite material 100 of this embodiment, after stirring for a predetermined time by the planetary ball mill or the like, the stirring is stopped and the magnetic composite material is cooled for a sufficient time. Thereby, the magnetic composite material which has the stable low coercive force can be produced. According to the earnest study by the present inventors, the predetermined time (cooling time) is preferably 30 minutes or more.

  By adopting this step, a magnetic composite material comprising a plurality of magnetic metal particles of the present invention and at least one selected from metal oxides, nitrides, carbides or fluorides can be obtained. It becomes possible to control the average particle diameter and further the average particle diameter of the plurality of magnetic metal particles on the surface.

  In addition, after the step of stopping the stirring for a predetermined time, a step of stirring by rotating the stirring of the planetary ball mill in the reverse direction may be used.

  Further, an alloy containing at least one magnetic metal selected from Fe, Ni and Co, and Mg, Al, Si, Ca, Zr, Ti, Hf, Zn, Mn, Ba, Sr, Cr, Mo, Ag, Ga , Sc, V, Y, Nb, Pb, Cu, In, Sn, a magnetic composite containing at least one element selected from rare earth elements and any of oxygen (O), nitrogen (N), and carbon (C) The step of producing a magnetic composite material having a larger diameter and the step of stopping stirring may be repeated a predetermined number of times by bringing the nanoparticles into a container and aggregating them together with a medium in a dry manner. Here, the predetermined number of times is, for example, two times or more, but is not particularly limited.

  Thereafter, the magnetic composite material 100 may be treated (heat treatment) in hydrogen for about 1 hour. Here, the temperature of the heat treatment is, for example, about 400 ° C.

  According to the magnetic composite material 100 of the present embodiment, a magnetic composite material having a low coercive force can be provided.

(Second Embodiment)
The present embodiment is an inductor element using the magnetic composite material according to the first embodiment. Here, the description overlapping with the first embodiment is omitted.

  FIG. 3 is a schematic diagram of the chip inductor element 200 of the present embodiment. A coil 102 is disposed inside the magnetic composite material 100. Both ends of the coil 102 are connected to two electrodes 108, respectively.

  FIG. 4 is a schematic diagram of the transformer inductor element 300 of the present embodiment. The transformer inductor element 200 has a configuration in which a first coil 104 and a second coil 106 are wound around a magnetic composite material 100 as shown in FIG. Electrodes (not shown) may be connected to both ends of the first coil 104 and both ends of the second coil 106.

  FIG. 4B shows how the flat orientation of the magnetic metal particles 10 in the transformer inductor element 300 of this embodiment is shown. When the magnetic metal particle 10 is a flat particle, the flat surface is preferably oriented in the xy plane as shown in FIG. This is because the magnetic permeability of the magnetic member in the axial direction of the first coil 104 and the axial direction of the second coil 106 can be further increased.

  According to the present embodiment, an inductor element capable of obtaining a high permeability with a small loss at a high frequency is provided.

  Hereinafter, examples will be described in more detail in comparison with comparative examples.

Example 1
FeNi having an average particle diameter of 100 nm is treated in an oxidizing atmosphere for 15 minutes in a dry planetary ball mill and then cooled for 30 minutes (stopping stirring by the dry planetary ball mill) is repeated for a total of 240 minutes to recover this. Thus, a magnetic composite material comprising a plurality of FeNi particles and at least one oxide of Fe and Ni, an average particle size of 40 μm, and an average particle size of magnetic metal particles observed on the surface of 30 nm is obtained. It was.

(Comparative Example 1)
FeNi having an average particle size of 50 μm is treated in a dry planetary ball mill in an oxidizing atmosphere for 15 minutes, and then cooled for 30 minutes. The treatment is repeated for a total of 60 minutes to recover a plurality of FeNi particles, Fe A magnetic composite material comprising at least one oxide of Ni, an average particle size of 40 μm, and an average particle size of magnetic metal particles observed on the surface of 100 nm was obtained.

(Example 1-2)
FeNi-Si with an average particle size of 50 nm is treated in an oxidizing atmosphere for 15 minutes with a dry planetary ball mill, then repeatedly cooled for 60 minutes, treated for a total of 180 minutes, recovered, and then treated in hydrogen for 1 hour. Thus, a magnetic material comprising a plurality of FeNi-Si particles and at least one oxide of Fe, Ni, and Si, an average particle size of 35 μm, and an average particle size of magnetic metal particles observed on the surface of 13 nm. A composite material was obtained.

(Example 2)
By treating FeNi with an average particle size of 50 nm for 15 minutes in a dry planetary ball mill in an oxidizing atmosphere, cooling for 60 minutes is repeated for a total of 120 minutes to collect a plurality of FeNi particles and Fe A magnetic composite material comprising at least one oxide of Ni, an average particle diameter of 20 μm, and an average particle diameter of magnetic metal particles observed on the surface of 20 nm was obtained.

(Comparative Example 2)
FeNi having an average particle size of 10 μm is treated for 15 minutes in a dry planetary ball mill in an oxidizing atmosphere, and then cooled for 60 minutes. The treatment is repeated for a total of 60 minutes to recover a plurality of FeNi particles, Fe A magnetic composite material comprising at least one oxide of Ni, an average particle diameter of 20 μm, and an average particle diameter of magnetic metal particles observed on the surface of 90 nm was obtained.

(Example 2-1)
By treating FeCo with an average particle size of 50 nm in an oxidizing atmosphere for 15 minutes in a dry planetary ball mill, cooling for 30 minutes is repeated for a total of 90 minutes to collect a plurality of FeCo particles and Fe A magnetic composite material comprising at least one oxide of Co and Co, having an average particle diameter of 15 μm and an average particle diameter of magnetic metal particles observed on the surface of 30 nm was obtained.

(Example 3)
FeNi-Si with an average particle size of 50 nm is treated in an oxidizing atmosphere for 15 minutes in a dry planetary ball mill, then cooled for 30 minutes, and the next treatment is repeated in reverse rotation. By treating in hydrogen for 1 hour, a plurality of FeNi-Si particles and at least one oxide of Fe, Ni, Si are included, and the particle diameter is 25 μm. A magnetic composite material having an average particle size of 15 nm was obtained.

(Comparative Example 3)
FeNi-Si with an average particle size of 50 μm was treated in an oxidizing atmosphere with a dry planetary ball mill for 15 minutes, then cooled for 30 minutes, and the next treatment was repeated in reverse rotation, and treated for a total of 120 minutes to recover this, By treating in hydrogen for 1 hour, it comprises a plurality of FeNi-Si particles and at least one oxide of Fe, Ni, Si, and has a particle diameter of 25 μm and an average of magnetic metal particles observed on the surface A magnetic composite material having a particle size of 110 nm was obtained. The coercive force of this magnetic material was measured and found to be 97 Oe.

(Example 3-2)
FeNi-Si with an average particle size of 50 nm is treated in an oxidizing atmosphere with a dry planetary ball mill for 15 minutes, then cooled for 30 minutes, and the next treatment is repeated in reverse rotation for a total of 120 minutes. In addition, in the same manner as dry type, it is processed in a total of 30 minutes in a wet process. After this is recovered, it is processed in hydrogen for 1 hour, so that a plurality of FeNi-Si particles and at least one oxide of Fe, Ni, and Si can be obtained. A magnetic composite material having a particle diameter of 25 μm and an average particle diameter of magnetic metal particles observed on the surface of 10 nm was obtained.

(Example 3-3)
FeNi-Si with an average particle size of 50 nm is treated in an oxidizing atmosphere with a dry planetary ball mill for 15 minutes, then cooled for 30 minutes, and the next treatment is repeated in reverse rotation for a total of 120 minutes. In addition, in the same way as dry, it is treated in a total of 120 minutes in a wet process. After this is recovered, it is treated in hydrogen for 1 hour, so that a plurality of FeNi-Si particles and at least one oxide of Fe, Ni, and Si are obtained. A magnetic material having a particle diameter of 40 μm and an average particle diameter of magnetic metal particles observed on the surface of 10 nm was obtained. The coercive force of this magnetic material was measured and found to be 15 Oe.

Example 4
FeNi-Al having an average particle size of 50 nm was treated in an oxidizing atmosphere for 15 minutes with a dry planetary ball mill, then cooled for 30 minutes, and the next treatment was repeated in reverse rotation. In the treatment for 1 hour, a magnetic composite material having a particle diameter of 25 μm and an average particle diameter of magnetic metal particles observed on the surface of 10 nm was obtained. When a cross-sectional TEM of the magnetic composite material was observed, the structure of the magnetic composite material was a hetero granular (HG) structure in which FeNi-rich magnetic metal fine particles were dispersed in a FeNiAlO oxide-rich matrix.

(Example 4-2)
FeCo-Si with an average particle size of 50 nm is treated in an oxidizing atmosphere for 15 minutes with a dry planetary ball mill, then cooled for 30 minutes, and the next treatment is repeated in reverse rotation. In the same manner as the dry process, the wet process is performed for 120 minutes. After recovering this, it is treated in hydrogen for 1 hour to obtain a magnetic composite material having a particle diameter of 0.5 μm and an average particle diameter of 10 nm of fine particles observed on the surface. Obtained. When a cross-sectional TEM of the magnetic composite material was observed, the structure of the magnetic composite material was a heterogranular (HG) structure in which FeCo-rich magnetic metal fine particles were dispersed in an FeCoSiO oxide-rich matrix.

(Example 5)
FeNi particles with an average particle size of 10 μm were treated in an oxidizing atmosphere for 15 minutes in a dry planetary ball mill, then cooled for 30 minutes, and the next treatment was repeated in reverse rotation. By treating for 1 hour, a magnetic composite material having a particle diameter of 40 μm and an average particle diameter of magnetic metal particles observed on the surface of 10 nm was obtained. When a cross-sectional TEM of the magnetic composite material was observed, the structure of the magnetic composite material was a heterogranular (HG) structure in which FeNi-rich magnetic metal fine particles were dispersed in an FeNi oxide-rich matrix.

(Example 5-2)
After processing the FeCr-Si particles with an average particle size of 50 nm in an oxidizing atmosphere for 15 minutes in a dry planetary ball mill, cooling for 30 minutes, and the next treatment is reverse rotation, and after processing for a total of 120 minutes, recovery, By treating in hydrogen for 1 hour, it comprises a plurality of FeCr-Si particles and at least one oxide of Fe, Cr, Si, and has a particle diameter of 35 μm and an average of magnetic metal particles observed on the surface A magnetic material having a particle size of 10 nm was obtained.

(Comparative Example 4)
By treating FeNi having an average particle size of 100 nm for 15 minutes with a wet planetary ball mill using acetone, cooling for 15 minutes is repeated for a total of 240 minutes to collect a plurality of FeNi particles, A magnetic material having at least one oxide of Fe and Ni, an average particle diameter of 40 μm, and an average particle diameter of magnetic metal particles observed on the surface of 19 nm was obtained. The 15-minute cooling is a predetermined machine cooling time that is normally performed.

(Comparative Example 5)
When FeNi with an average particle size of 100 nm was treated in an oxidizing atmosphere for 15 minutes with a dry planetary ball mill and then cooled for 15 minutes, the treatment was repeated for a total of 240 minutes. It was difficult to recover. The 15-minute cooling is a predetermined machine cooling time that is normally performed.

  About the magnetic composite material obtained by each Example and the comparative example, the measurement of the coercive force (Oe), the crystal diameter (nm) measured by XRD, and the aspect ratio of the magnetic composite material were measured. Table 1 summarizes the results of the examples and comparative examples.

  As shown in Table 1, in Comparative Examples 1, 2, and 3, the coercive force is as large as 85 Oe, 55 Oe, and 97 Oe because the particle size of the raw material before processing with the dry planetary ball mill is as large as 50 μm, 10 μm, and 50 μm. It was. In Comparative Example 3-2, since the aspect ratio was as large as 10, the coercive force was as large as 15 Oe. (In Example 3-2, the aspect ratio is reduced to reduce the coercive force) In Comparative Example 4, it is wet stirring using acetone, and a predetermined time for cooling (predetermined to stop stirring by the planetary ball mill) ) Was as short as 15 minutes, and the coercive force became as large as 70 Oe. In Comparative Example 5, it was dry stirring, but since the cooling time (predetermined time for stopping stirring by the planetary ball mill) was as short as 15 minutes, almost all the material adhered and collected in the ball and the container. It was difficult. In other examples, good results were obtained.

  Table 2 shows the relationship between the aspect ratio and Hc (coercive force).

  As shown in Table 2, the smaller the aspect ratio, the smaller the coercive force, and a coercive force of 9.4 Oe with an aspect ratio of 5 and 7.5 Oe with an aspect ratio of 2 was obtained.

  According to the magnetic material of at least one embodiment described above, a plurality of magnetic metal particles including at least one magnetic metal selected from Fe, Ni and Co, and an oxidation provided around the plurality of magnetic metal particles And an insulator containing nitride, nitride, carbide, or fluoride, wherein the magnetic material has a particle size of 0.1 μm or more and 40 μm or less, and an average of a plurality of magnetic metal particles on the surface of the magnetic material By having a particle size of 80 nm or less, a magnetic material having a low coercive force can be provided.

  Although several embodiments and examples of the present invention have been described, these embodiments and examples have been presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

DESCRIPTION OF SYMBOLS 10 Magnetic metal particle 20 At least 1 sort (s) chosen from metal oxide, nitride, carbide, or fluoride 100 Magnetic material 102 Coil 104 First coil 106 Second coil 108 Electrode 200 Chip inductor element 300 Inductor element for transformer

Claims (7)

A magnetic composite material comprising a plurality of magnetic metal particles containing at least one magnetic metal selected from Fe, Ni, and Co, and at least one selected from metal oxides, nitrides, carbides, or fluorides. And
A magnetic composite material in which an average particle diameter of the magnetic composite material is 0.1 μm or more and 40 μm or less, and an average particle diameter of the plurality of magnetic metal particles on the surface of the magnetic composite material is 80 nm or less.   The magnetic composite material according to claim 1, wherein a crystal diameter of the magnetic metal particles is 1 nm or more and 50 nm or less.   The magnetic composite material according to claim 1, wherein an aspect ratio of the magnetic composite material is 1 or more and 5 or less.   The metal oxide, nitride, carbide or fluoride is Fe, Ni, Co, Mg, Al, Si, Ca, Zr, Ti, Hf, Zn, Mn, Ba, Sr, Cr, Mo, Ag, Ga. 4. The magnetic composite material according to claim 1, comprising at least one element selected from the group consisting of: Sc, V, Y, Nb, Pb, Cu, In, Sn, and a rare earth element.   An inductor element using the magnetic composite material according to any one of claims 1 to 4.   An alloy containing at least one magnetic metal selected from Fe, Ni and Co, and Mg, Al, Si, Ca, Zr, Ti, Hf, Zn, Mn, Ba, Sr, Cr, Mo, Ag, Ga, Sc , V, Y, Nb, Pb, Cu, In, Sn, magnetic composite nanoparticles containing at least one element selected from rare earth elements and any of oxygen (O), nitrogen (N), and carbon (C) A method for producing a magnetic composite material comprising a step of producing a magnetic composite material having a larger diameter by aggregating and integrating together by agitating together with media in a dry manner in a container.   The method for producing a magnetic composite material according to claim 6, further comprising a step of stopping the stirring for a predetermined time.